[Dev] Fix Qwen3-Next hang on Blackwell, add a flag to control torch.compile

[yuzhongw-nvidia]

What does this PR do ?

torch.compile is not very well supported on Blackwell, and may cause Qwen3-Next hanging when training on Blackwell. Add a flag in arguments to disable it.

With triton>=3.4.0, this fix PR, and the following extra arguments, the issue will be resolved.

  --disable-jit-fuser \
  --no-bias-gelu-fusion \
  --no-bias-swiglu-fusion \
  --no-bias-dropout-fusion

⚠️ For major changes (either in lines of code or in its impact), please make sure to first share discuss a design-doc with the team.

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flowchart LR
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    subgraph Code Review/Approval
        C1[Expert Review] --> C2[Final Review]
    end
    B --> C1
    C2 --> D[Merge]

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[yuzhongw-nvidia]

/ok to test 9a2ce88

[yuzhongw-nvidia]

/ok to test 6a68816

[yuzhongw-nvidia]

/ok to test 158e53b